1. Field of the Invention
The present invention relates to a slide fastener chain having one end shaped to facilitate threading thereof into a slider, and a method of and a cutter for manufacturing such a slide fastener chain.
2. Prior Art
There have been known various individual or discrete slide fastener chains cut to lengths for consumer use and continuous slide fastener chains of factory-produced lengths not yet severed for individual use. The prior slide fastener chains, discrete or continuous, have ends cut transversely as straight edges or notched to remove an intermeshing portion from coupling elements. When the slide fastener chain with the straight or flat end is threaded through a slide fastener slider, intermeshing coupling elements at the flat chain end fail to separate easily or tend to remain coupled upon abutting against a connector post or separator in the slider. Another disadvantage experienced with the flat-end chain in the slider mounting process is that the chain end provides only a limited area that the operator can grip with finger-nail tips, but not fingers, and hence the slide fastener chain cannot be pulled through the slider with a sufficient force. This slider mounting operation is time-comsuming, less efficient, and frequently yields defective slide fastener products.
The slide fastener chain with the notched end is more advantageous in that coupling elements can smoothly be disengaged by the separator in the slider, and the notched end of the chain has a wider tape portion for the operator to grasp more firmly in threading the chain through the slider. However, where the coupling elements are sewn by sewing threads to the stringer tapes, coupling element debris on the notched end is liable to loosen and thus become staggered as the sewing threads unravel, preventing the chain from being introduced into the slider. The sewing threads as they unravel when the stringer tapes are cut off can get caught between the slider and coupling elements, making chain threading through the slider sluggish or impossible.